Gros Ventre Slide, Wyoming

The Gros Ventre slide may have been started by heavy prolonged
rainfall. Some 50 million cubic yards of sandstone, limestone, shale and
rock, about one mile long, 2000 feet wide and several hundred feet deep in
places, plunged down and formed a dam 225 feet high and half a mile wide
across the Gros Ventre River. A lake was created above the dam.

For almost two years this earth dam held; then on May 18, 1927, part of
the dam gave way and a wall of water, mud and rock flowed down the canyon
destroying valuable property. Ranch lands were ruined by mud and rubble
and the town of Kelly, three and one half miles downstream, was
practically wiped out. Six persons drowned.

The Gros Ventre slide is located just east of Grand Teton
National Park. Above: views of the landslide scar from the west.

Left: looking west down the valley of the Gros Ventre River toward the
Tetons.

Beyond the foreground ridge in the photo above, the land is
flat. The town of Kelly, mentioned in the historical marker above, is a
small collection of buildings with no obvious signs of the flood.

Slide Lake, looking east (upstream)

Slide Lake looking southwest to the slide.

Left and below: views of the slide. The slide itself is
forested and may have transported much of the forest cover intact. The
slide scar is still largely bare even after three quarters of a century,
probably because the surface is largely bedrock devoid of soil.